Traits

Traits linked to GJA8

gap junction protein alpha 8

The Human Phenotype Ontology links 104 traits to GJA8, by body system: features seen in people with one of the gene's rare conditions.

Abnormality of head or neck

Trait	How often it is seen
Abnormally small head	Often (30–79%)
Broad head shape	Sometimes (5–29%)
Decreased volume of lip	Sometimes (5–29%)
Depressed nasal bridge	Sometimes (5–29%)
Eye folds	Sometimes (5–29%)
Full lower lip	Sometimes (5–29%)
High palate	Sometimes (5–29%)
Little lower jaw	Sometimes (5–29%)
Low hanging columella	Sometimes (5–29%)
Prominent nasal bridge	Sometimes (5–29%)
Short neck	Sometimes (5–29%)
Thin red part of the upper lip	Sometimes (5–29%)
Upward slanting of the opening between the eyelids	Sometimes (5–29%)
Bifid uvula	Rarely (1–4%)
Big lower jaw	Rarely (1–4%)
Decreased size of tooth	Rarely (1–4%)
Highly arched eyebrow	Rarely (1–4%)
Long lower eyelashes	Rarely (1–4%)
Long philtrum	Rarely (1–4%)
Monobrow	Rarely (1–4%)
Nasal tip, upturned	Rarely (1–4%)
Pointed chin	Rarely (1–4%)
Prominent back of the head	Rarely (1–4%)
Prominent forehead	Rarely (1–4%)
Prominent metopic ridge	Rarely (1–4%)
Prominent nose	Rarely (1–4%)
Round face	Rarely (1–4%)
Short opening between the eyelids	Rarely (1–4%)
Smooth philtrum	Rarely (1–4%)
Tall shaped head	Rarely (1–4%)
Triangular face	Rarely (1–4%)
Widely spaced teeth	Rarely (1–4%)
Zygomatic flattening	Rarely (1–4%)
Bulbous nose	Not recorded
Frontal bossing	Not recorded

Abnormality of the eye

Trait	How often it is seen
Pulverulent cataract	Always
Yellowish cloudy center of lens	Always
Clouding of the lens of the eye	Very often (80–99%)
Cornea of eye less than 10mm in diameter	Very often (80–99%)
Close sighted	Often (30–79%)
Cat eye	Sometimes (5–29%)
Corneal dystrophy	Sometimes (5–29%)
Corneal opacity	Sometimes (5–29%)
Cross-eyed	Sometimes (5–29%)
Deeply set eye	Sometimes (5–29%)
Farsightedness	Sometimes (5–29%)
Involuntary, rapid, rhythmic eye movements	Sometimes (5–29%)
Abnormally close eyes	Rarely (1–4%)
Abnormally small eyeball	Rarely (1–4%)
Duane anomaly	Rarely (1–4%)
Esodeviation	Rarely (1–4%)
Exophoria	Rarely (1–4%)
Nuclear pulverulent cataract	Rarely (1–4%)
Sutural cataract	Rarely (1–4%)
Wide-set eyes	Rarely (1–4%)
Posterior subcapsular cataract	Not recorded

Abnormality of limbs

Trait	How often it is seen
Curvature of little finger	Sometimes (5–29%)
Single transverse palmar crease	Sometimes (5–29%)
Broad big toe	Rarely (1–4%)
Broad thumb	Rarely (1–4%)
Central polydactyly of feet	Rarely (1–4%)
Dropped arches	Rarely (1–4%)
Duplication of thumb phalanx	Rarely (1–4%)
Overlapping toe	Rarely (1–4%)
Prominent fingertip pads	Rarely (1–4%)
Short fingers or toes	Rarely (1–4%)
Short outermost finger bone	Rarely (1–4%)
Talipes	Rarely (1–4%)

Abnormality of the nervous system

Trait	How often it is seen
Global developmental delay	Often (30–79%)
Epilepsy	Sometimes (5–29%)
Repetitive movements	Sometimes (5–29%)
Autism	Rarely (1–4%)
Behavioral abnormality	Rarely (1–4%)
Brief seizures with staring spells	Rarely (1–4%)
Delayed speech and language development	Rarely (1–4%)
Grand mal seizures	Rarely (1–4%)
Self-injurious behavior	Rarely (1–4%)
Tremor	Rarely (1–4%)
Intellectual disability	Not recorded
Schizophrenia	Not recorded

Abnormality of the cardiovascular system

Trait	How often it is seen
Patent ductus arteriosus	Sometimes (5–29%)
An opening in the wall separating the top two chambers of the heart	Rarely (1–4%)
Aortic regurgitation	Rarely (1–4%)
Aortic valve has two leaflets rather than three	Rarely (1–4%)
Bulging of wall of large artery located above heart	Rarely (1–4%)
Muscular ventricular septal defect	Rarely (1–4%)
Narrowing of aorta	Rarely (1–4%)
Palmoplantar erythema	Rarely (1–4%)
Perimembranous ventricular septal defect	Rarely (1–4%)
Transposition of the great arteries	Rarely (1–4%)
Truncus arteriosus	Rarely (1–4%)

Abnormality of the musculoskeletal system

Trait	How often it is seen
Double-Jointed	Sometimes (5–29%)
Low muscle tone	Sometimes (5–29%)
Funnel chest	Rarely (1–4%)
Low muscle tone in trunk	Rarely (1–4%)
Permanent flexion of the finger or toe	Rarely (1–4%)
Scoliosis	Rarely (1–4%)

Abnormality of the ear

Trait	How often it is seen
Low-set ears	Rarely (1–4%)
Prominent ear	Rarely (1–4%)
Sensorineural hearing impairment	Rarely (1–4%)
Simple ear	Rarely (1–4%)

Growth abnormality

Trait	How often it is seen
Faltering weight	Rarely (1–4%)
Truncal obesity	Rarely (1–4%)

Abnormality of the integument

Trait	How often it is seen
Frontal balding	Rarely (1–4%)

How often is among people with one of the gene's conditions, the most often across them, as the Human Phenotype Ontology records it. These pages describe traits and the research behind them; they are not a diagnosis, and a doctor or genetic counsellor is the person to ask about symptoms.

Where this comes from

The Human Phenotype Ontology, release 2026-09-01: the traits linked to GJA8 and how often each is seen. Find out more at hpo.jax.org.

One test. A lifetime of answers.

From $449Free shipping · Results in 6–8 weeks

Get my Genome Test